Inappropriate Prescribing as a Predictor for Long-Term Mortality after Hip Fracture

Abstract

Background: Hip fracture patients are at a higher risk for death compared to age-matched controls. While the reasons for this increased mortality risk are incompletely understood, medical comorbidities and associated medication prescribing likely play an important role in patient outcomes. Altered drug metabolism, polypharmacy and diminished physiologic reserve may all lead to adverse drug reactions and adverse outcomes. Additionally, underprescribing of efficacious medications may deprive older patients of potential therapeutic benefits. Objective: The aim of our trial was to estimate the impact of inappropriate medication prescribing on the long-term outcome of older hip fracture patients. Methods: The present study is a retrospective cohort study. We included all hip fracture patients who were consecutively admitted to our department from 2000 to 2004. We used the previously published STOPP (Screening Tool of Older Person's Prescriptions) and START (Screening Tool to Alert doctors to Right Treatment) criteria to assess the appropriateness of medication prescribing with an additional focus on osteoporosis medications and the total number of prescriptions. Prescriptions meeting STOPP and START criteria were considered ‘positive items' and correlated with outcomes. Mortality was assessed by cross-referencing with the national death registry of the Tyrolean Institute of Epidemiology. Results: During the study period, a total of 457 patients with hip fracture (mean age 80.61 ± 7.07 years; range 65-98) were evaluated. The mean number of positive combined STOPP and START items per patient was 2 ± 1.3, with ranges from 0 to 6 (STOPP items), 0 to 4 (START items) and 0 to 7 (combined STOPP/START items). Only 44 (9.6%) of patients had no positive STOPP or START items. The mean number of positive items (STOPP, START and combined) was significantly higher in non-survivors than survivors. The all-cause mortality rate at 3 years was lowest in the subjects with 1 or 0 positive items (20.5%; n = 35) and highest among those with >3 positive items (44.4%; n = 63). Inappropriate medication prescribing remained an independent risk factor with an odds ratio of 1.28 (1.07-1.52) after adjustment for sex, age, activities of daily living, comorbidities and nutrition status. Conclusion: Inappropriate medication prescribing is an independent predictor of long-term mortality in older hip fracture patients. It increases the relative risk of mortality in older hip fracture patients by 28%.